Work in this competing continuation builds on that previously undertaken which compiled and analyzed data from the 12-site WHO Collaborative Study on Alcohol and Injuries with that from 33 ER sites in 8 countries comprising the Emergency Room Collaborative Alcohol Analysis Project (ERCAAP), all of which used similar methodology and instrumentation on probability samples of ER patients. Study aims include: 1) examine the magnitude of the association of alcohol and injury and risk of alcohol- related injury in relation to drinking pattern, type and cause of injury, dose-response relationship, severity and disability of injury, context of injury, and drug use;2) compare and adjust estimates of relative risk of injury from alcohol across various control periods used in case-crossover analysis;3) improve estimates of alcohol attributable fraction (AAF) and injury;4) investigate the relationship between BAC, overall clinical assessment of intoxication, and individual clinical signs of intoxication. This competing continuation will explore in more depth the association of alcohol and injury with a broader array of contextual variables, and gaps in this research which were identified at an international conference on alcohol and injury, (Cherpitel, Principal Investigator) sponsored by NIAAA and co-sponsored by WHO and CDC in October 2005, and follows recommendations presented at the October 2006 NIAAA Extramural Advisory Board on improving AAF for injury morbidity, a key priority identified for the Division of Epidemiology and Prevention Research. The proposed research will add to the WHO/ERCAAP dataset of 11,536 injured and 10,036 non-injured patients, 36 ER sites from 13 countries (for a total of 25 countries), including 11 U.S. sites, and 3 sites comprising the PAHO Collaborative Study, more than doubling the number of injury cases (to over 34,000) and increasing the non-injured cases to over 14,500. Addition of these sites will result in a data file on variables of interest on all known probability samples of ER patients, internationally, not only increasing the number of patients required for addressing study aims, but also providing data not presently available in the WHO/ERCAAP, and providing a broader representation of ERs, internationally and domestically, with expanded representation important for contextual analysis. Community and regional general population data will also be added, available from 76 of the 81 ER sites, including data from GENACIS, which will allow us to carry out important work on AAF and injury, including refining contextual variables and their predictive value for relative risk estimates and providing contextual profiles for assigning AAFs for countries for which ER data are not available. Hierarchical linear modeling, case-crossover and meta- analysis will be used to examine the independent and interactive effects of contextual variables with individual- and event-level variables. These cross-national analyses will address important gaps in the alcohol-injury nexus worldwide and in the US, since the US is composed of many micro-cultures which reflect the contextual environment dominating many of the countries in which these data were collected. PUBLIC HEALTH RELEVANCE: This work is especially relevant to public health issues in relation to allowing us to apply estimates of alcohol attributable fraction from countries which reflect a specific contextual profile to other countries with similar contextual profiles for which ER data are not available but for which general population data are. This research is important for the ongoing work on Comparative Risk Assessment, resulting from the World Health Assembly 2005 Resolution on Alcohol in determining the Global Burden of Disease related to alcohol.